Q: As already mentioned, the TB pathogen was discovered by Robert Koch. How did this come about?
Gerste: Along with cholera, TB was a great epidemic of the 19th century. For an ambitious researcher like Robert Koch, who had made a name for himself with the discovery of anthrax in 1876, there was no more rewarding goal than to find the cause of this infectious disease, which claimed the lives of many famous people such as Kafka, Dostoevsky, and Schiller, as well as many whose names are forgotten today.
[Dr.] Koch worked with his cultures for several years; the method of staining with methylene blue that was developed by the young Paul Ehrlich represented a breakthrough. To this method, [Dr.] Koch added a second, brownish dye. After countless experiments, this allowed slightly curved bacilli to be identified in tuberculous material under the microscope.
On the evening of March 24, 1882, [Dr.] Koch gave a lecture at the Institute of Physiology in Berlin with the title “Etiology of TB,” which sounded less than sensational on the invitations. One or two dozen participants had been expected, but more than one hundred came; numerous listeners had to make do with standing room behind the rows of chairs in the lecture hall. After a rather dry presentation ([Dr.] Koch was not a great orator nor a self-promoter), he presented his results to those present.
His assistants had set up a series of microscopes in the lecture hall through which everyone could get a glimpse of this enemy of humanity: the tubercle bacillus. When [Dr.] Koch had finished his remarks, there was silence in the hall. There was no burst of applause; the audience was too deeply aware that they had witnessed a historic moment. Paul Ehrlich later said that this evening had been the most significant scientific experience of his life. Over the next few weeks, the newspapers made a national hero out of Robert Koch, and the Emperor appointed him a Privy Councilor of the Government. The country doctor from Pomerania was now the figurehead of science in the young German Empire.
Q: Shortly after his discovery, [Dr.] Koch advertised a vaccination against TB with the active ingredient tuberculin. Was he able to convince with that too?
Gerste: No, this was the big flop, almost the disaster of a remarkable scientific career. The preparation of attenuated tubercle bacilli with water and glycerin not only did not prevent infection at all, it proved fatal for numerous users. However, tuberculin has survived in a modified form: as a tuberculin test, in which a characteristic skin rash indicates that a tested person has already had contact with the Mycobacterium.
Q: How have diagnostic options and treatment of the disease evolved since Robert Koch’s lifetime?
Gerste: A very decisive advance was made in diagnostics. With the rather accidental discovery of the rays soon named after him by Wilhelm Conrad Röntgen in the last days of 1895, it became possible to visualize the lung changes that tuberculosis caused in an unexpected way on living patients; the serial examinations for TB by X-rays were the logical consequence. Both scientists received Nobel Prizes, which were still new at the time, within a few years of each other: [Dr.] Röntgen in 1901 for physics, and [Dr]. Koch in 1905 for medicine and physiology.
Effective drugs were practically unavailable toward the end of the 19th century. For those who could afford it, however, a whole new world of (hoped-for or perceived) healing from “consumption” opened up: the sanatorium, located high in the mountains, surrounded by “fresh air.” The most famous of these climatic health resorts is probably Davos. It is no disrespect to the Swiss Confederation, which I hold in high esteem, to point out that Switzerland owes its high status as a tourist destination and thus its prosperity in part to TB.